APPARATUS FOR POSITIONING LIGHT OBJECT

A device for positioning objects which have a low mass, especially for positioning magnetic heads over preselected magnetic tracks on at least one magnetic disk, which can be coupled to a drive, in a memory processing unit, in which a carriage, which is capable of being moved toward and away from the axis of rotation of the magnetic disk, carries at least one magnetic head, this carriage being so mounted between guide elements that it can be displaced by a drive motor longitudinally with respect to the chassis of the unit, wherein the guide elements, in particular pairs of anti-friction bearings, engage either side of the carriage, at least one of the pairs of anti-friction bearings being gimbal-mounted in order to counteract any tilting moments which may act on the carriage. The device advantageously includes a band-type drive mechanism for displacing the carriage, comprising a rotatable cylindrical member around which the band means is wound and which may serve as an additional bearing element. The novel device can be used with advantage in any type of positioning system, especially in any type of system for storing video signals, data signals, audio signals or control signals and having high track densities.